When two user equipment terminals (e.g., mobile communication devices) of a cellular network or other telecommunication system communicate with each other, their data path typically goes through the operator network. The data path through the network may include base stations and/or gateways. If the devices are in close proximity with each other, their data path may be routed locally through a local base station. In general, communications between a network node such as a base station and a wireless terminal is known as “WAN” or “Cellular communication”.
It is also possible for two user equipment terminals in close proximity to each other to establish a direct link without the need to go through a base station. Telecommunications systems may use or enable device-to-device (“D2D”) communication, in which two or more user equipment terminals directly communicate with one another. In D2D communication, voice and data traffic (referred to herein as “communication signals” or “communications”) from one user equipment terminal to one or more other user equipment terminals may not be communicated through a base station or other network control device of a telecommunication system. “Device-to-device (“D2D”) communication may also be known as “sidelink direct” communication (e.g., sidelink communication), or even as “sidelink”, “SL”, or “SLD” communication.
D2D or sidelink direct communication can be used in networks implemented according to any suitable telecommunications standard. A non-limiting example of such as standard is the 3rd Generation Partnership Project (“3GPP”) Long Term Evolution (“LTE”). The 3GPP standard is a collaboration agreement that aims to define globally applicable technical specifications and technical reports for third and fourth generation wireless communication systems. The 3GPP may define specifications for next generation mobile networks, systems, and devices.
Currently 3GPP is specifying a new feature for Rel-14 that covers use cases and potential requirements for LTE support for vehicular communications services (represented by the term, Vehicle-to-Everything (V2X) Services). The feature is documented in the TR 22.885 on LTE Study on LTE Support for V2X Services. Contemplated V2X services may include one or more of the following:                V2V: covering LTE-based communication between vehicles.        V2P: covering LTE-based communication between a vehicle and a device carried by an individual (e.g. handheld terminal carried by a pedestrian, cyclist, driver or passenger).        V2I: covering LTE-based communication between a vehicle and a roadside unit. A roadside unit (RSU) is a transportation infrastructure entity (e.g. an entity transmitting speed notifications).        
Thus far 3GPP deliberations concerning resource pool design have essentially assumed that a similar resource pool construction will be used for V2X as has been used for LTE sidelink, e.g., have assumed that Rel-12 and Rel-13 D2D resource pool design would be the baseline of V2X design. However, there are numerous and challenging differences between V2X and DSL (D2D), as discussed below.
Sidelink direct (SLD) resource allocation is primarily either through SIB18 broadcast signaling, or dedicated signaling, or pre-configuration. Regardless of which of these three manners of resource allocation are employed, the SLD resource pool design only considers priority for resource differentiation. For example, SLD resource allocation does not include any collision avoidance mechanism when such as when wireless terminals attempt to use the same resources at the same time as well.
By contrast, in V2X communications the resource usage situation becomes much more complicated, for many reasons. Once such reason is that there will be many more wireless terminals in areas such as a city center. Another reason is that traffic situations may vary time by time even in the same area, or dramatically changes due to some accidental events. When such situations occur, whether the original allocated resources remain sufficient, or how to make the best use of the current resources with least collision, will be problematic.
3GPP discussions have been extended to such problems, e.g., “Sets of resources among which a UE selects can be restricted based on the geo information of the UE. Send LS to RAN2 asking them to enable mapping a set of locations to a set of resources”. Details of 3GPP discussions are referred in background part. Note that it was agreed that besides “Geo-information (e.g. vehicle location)” which will be sent from UE to eNB for resource allocation, other information can also be reported to eNB.
What is needed are methods, apparatus, and/or techniques for controlling resource assignment and utilization in vehicle (V2X) communications.